BlueMapPortalMarkers

See every Nether portal on your BlueMap web map, automatically.

BlueMapPortalMarkers adds a toggleable Nether Portals layer to BlueMap and keeps it in sync with your world. Portals appear the moment they're lit, get discovered as players explore, and disappear when broken. No commands to memorize, no manual marker editing, no spreadsheet of coordinates.

✨ Features

• 🔵 A live "Nether Portals" layer in BlueMap. Every portal becomes a clickable marker. Players toggle the whole layer on or off from BlueMap's marker menu.
• ⚡ Automatic detection. Portals are picked up four ways, all merged into one clean list:
  • New portals appear instantly when a frame is lit or created by nether-pairing.
  • Existing portals are found by a startup sweep around spawn and online players.
  • Roaming coverage quietly fills in portals as players explore new chunks.
  • Broken portals are removed automatically when their blocks are destroyed.
• 🧭 Portal linking (Overworld ↔ Nether). Each popup shows the predicted counterpart in the other dimension using the vanilla 8:1 rule, and when that counterpart is already on the map, a "Go to linked portal" button flies the viewer straight to it.
• 🔁 No duplicates, ever. However many times a portal is detected, it shows up as exactly one marker, frames of any size are handled correctly.
• 💾 Persists across restarts. Discovered portals are saved to disk and re-drawn automatically whenever BlueMap reloads.
• 🛠️ Admin commands. Force a sweep, view per-world portal counts, purge stale markers, and hot-reload settings without restarting the server.
• 🎛️ Highly configurable. Per-world filtering, custom marker icon and label, visibility distance, optional background sweeping, and more, most of it applied live with /bmportals reload.
• 🪶 Lightweight. Detection rides on data Minecraft already tracks, so it stays cheap even on busy servers.

📋 Requirements

🚀 Quick start

1. Download the latest BlueMapPortalMarkers-<version>.jar.
2. Drop it into your server's plugins/ folder, alongside BlueMap.
3. Restart the server. A config file is created on first run.
4. Open BlueMap and toggle the Nether Portals layer in the marker menu. Done!

Existing portals near spawn show up on the first sweep; the rest appear as players roam, or you can run /bmportals sweep to scan immediately.

⚙️ Configuration highlights

Everything lives in plugins/BlueMapPortalMarkers/config.yml. A few favourites:

• markers.label / markers.icon: rename the layer and give it a custom icon.
• discovery.sweep-radius: how far the startup sweep reaches around spawn and players.
• discovery.worlds: whitelist or blacklist worlds (skip creative or minigame worlds).
• linking.enabled: turn the Overworld↔Nether predicted-link section on or off.
• discovery.background-sweep: opt-in periodic re-sweeping for always-fresh coverage.

💡 The clickable "Go to linked portal" deep-link needs a one-time BlueMap web-app tweak (two small files BlueMap ships in the box). Everything else (markers, popups, predicted-link text) works with zero web setup. See the README for the 3-step guide.

🎮 Commands

All /bmportals subcommands require the bmportals.admin permission (ops by default).

⚠️ Good to know

• Paper 26.1.2+ only. There's no Spigot or older-Paper fallback.
• Portals in never-touched pre-1.14 regions may not appear until those chunks are loaded by the game.
• The startup sweep covers a radius around spawn and players, not the entire world. Roaming coverage and background sweeping fill in the rest over time.

📊 Privacy

Ships with anonymous, aggregate usage stats via bStats (metrics.enabled in the config, or opt out server-wide). No personal or world data is ever collected.

🆓 Open source

BlueMapPortalMarkers is free software under the GNU GPL v3.0. Source, issues, and releases live on GitHub.